1. Field of the Invention
The present invention relates to an imaging apparatus and method thereof, more particularly to a method and an imaging apparatus including monochrome and multi-color image detection devices for scanning an object in order to obtain a 3-dimensional profile image with monochrome or multi-color of the object or a planar distinctive image with monochrome or multi-color of the object.
2. Description of the Prior Art
In the prior art 3-dimensional micro scanning method, an interferometry system is generally applied in order to obtain an image so that the image thus obtained usually consists of interference fringes. Though a 3-dimensional profile of an object to be scanned can be achieved by means of the interferometry system, but we cannot directly detect or measure by the interference fringe or the disadvantages of the 2-dimensional image.
In order to solve the abovementioned problem, two novel methods have been implemented lately; namely: (1) Phase shifting method and (2) Modulating method. FIG. 1 shows a schematic view of a prior art imaging apparatus 100, which includes a light source 11, a beam splitter 12, an interferometer 13, a monochrome camera 14 and an actuator 15. The prior art imaging apparatus 100 is disposed right above an object 200 for scanning the same.
The light source 11 is capable of emitting a projection beam 31. The beam splitter 12 reflects the projection beam 31, thereby forming a reflection beam 32. The interferometer 13 modulates the reflection beam 32 via a reflection reference surface 131 into a reference beam 33 and a measurement beam 34 such that the measurement beam 34 is radiated onto an outer surface of the object 200 to be scanned, reflects back into the interferometer 13, and mixes with the reference beam 33 so as to generate an interferometric beam 35, which pass through the beam splitter 12 and the monochrome camera 14, thereby forming a final image.
During the scanning operation, the actuator 15 activates the interferometer 13 so as to scan the object 200 from different scanning positions, thereby obtaining a series of interferometric image. This series of interferometric image undergoes a prosecution process, which results in a 3-dimensional image of the object 200 to be scanned. Later, after undergoing a combined execution process, a 2-dimensional distinctive image can be obtained when the interference fringes are excluded and this method is known as “phase shifting method”. The 2-dimensional image obtained via the phase shifting method does not have color information so that the image is a monochrome image since the objective lens unit provides a relatively small depth of field. Therefore, the topography profile of the 2-dimensional image of the scanned object is distinct due to the scanning operation from the high scan positions while the remaining parts of the 2-dimensional image are blurred.
In the modulating method, after the prior art imaging apparatus 100 obtaining a series of the interferometric image, the actuator 14 shifts and modulates the monochrome camera 14 into a proper imaging position so that the imaging apparatus 100 can obtain the final image, thereby achieving the 2-dimensional distinctive image of the scanned object 200.
In the abovementioned method, since the 3-dimensional profile image and the 2-dimensional image are separately fetched, the entire process includes several extra steps and undesired operations. Thus, the problem of relatively small depth of field and absent of color information in the 2-dimensional image are similarly present in this modulating method.